我将 c# windows 应用程序与 Access 数据库 (accdb) 连接，但该应用程序在其他计算机上不起作用

Question

I connected an Access database (accdb) with C#-windows application project. The "accdb" database is located in a folder in desktop. It works correctly on my computer but when i build a setup file and installed it on other computer the software didn't work. (i know the problem is that the database located in the folder) but i dont't know how to change the code that after installation on other computer, it can still connect to the database. Does anyone know how should i solve this problem? Here is the simple connection that i wrote:

OleDbConnection con = new OleDbConnection(@"Provider=Microsoft.ACE.OLEDB.12.0;Data Source=C:\Users\aa\Test.accdb;Jet OLEDB:Database Password=123;");

Answer 1

It works correctly on my computer but when i build a setup file and installed it on other computer the software didn't work.

The primary reason for this is because that path doesn't exist on the other machine; you've hard-coded your path.

 OleDbConnection con = new OleDbConnection(@"Provider=Microsoft.ACE.OLEDB.12.0;Data Source=C:\Users\aa\Test.accdb;Jet OLEDB:Database Password=123;");

C:\\Users\\aa\\Test.accdb this is the actual issue, you shouldn't hard code this value, instead you have two options I can think of.

1. Look for the file along side the application where it is being executed from (this requires the file to be inside the same directory the exe is in).
2. You could allow the end user to enter the location of that file, if it exist, save this path to use again when needed.

You can use either or I mention above and or do both of them, your choice. Below is a simple example using option one above.

using System.Reflection;
using System.IO; 

public static string GetDBConnection()
{
   try
   {
      string dbExecPath = Path.Combine(Path.GetDirectoryName(Assembly.GetExecutingAssembly().Location), "Test.accdb");
      return $"Provider=Microsoft.ACE.OLEDB.12.0;Data Source={ dbExecPath };Jet OLEDB:Database Password=123;";
   }
   catch (Exception)
   {
      return string.Empty;
   }            
}

This get's the assemblies location (path) and combines it with your file name (db file). Then combine's that with your other connection string parts and return's the whole connection string.

Please Note: the namespaces that have to be used and the db file must be in the same directory that the exe is if going this route.

Now you can call it like this:

 OleDbConnection con = new OleDbConnection(GetDBConnection());

You may want to assign the GetDBConnection() to a var and check if it's empty before constructing your connection, it may be empty.